📈 Compound Interest

$500 at 5% for 20 Years

Investing $500 at 5% annual compound interest for 20 years grows to $1,327. That's $827 earned in interest on top of your original $500.

Compound Interest Calculator
Australia 2026
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%
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Total value after 20 years
$1,327
Amount invested$500
Interest earned$827
Interest multiplier2.65×
Year-by-year growth
YearBalanceInterest
Yr 1$525+$25
Yr 2$551+$26
Yr 3$579+$28
Yr 4$608+$29
Yr 5$638+$30
Yr 6$670+$32
Yr 7$704+$34
Yr 8$739+$35
Yr 9$776+$37
Yr 10$814+$39
Yr 11$855+$41
Yr 12$898+$43
Yr 13$943+$45
Yr 14$990+$47
Yr 15$1,039+$49
Yr 16$1,091+$52
Yr 17$1,146+$55
Yr 18$1,203+$57
Yr 19$1,263+$60
Yr 20$1,327+$63
Final balance after 20 years
$1,327
Invested
$500
Interest earned
$827
Multiplier
2.65×

How $500 grows at 5%

Compound interest earns returns on your returns — not just your original investment. At 5% per year, your money doubles every 14.4 years (the Rule of 72). Over 20 years, that compounds to a 2.65× multiplier.

In year 1, $500 earns $25 in interest. By year 20, the annual interest has grown to $63 — because each year's interest is calculated on a larger balance.

$500 for 20 years at different rates
RateFinal balanceInterest earnedMultiplier
4%$1,096$5962.19×
5% ◀$1,327$8272.65×
6%$1,604$1,1043.21×
7%$1,935$1,4353.87×
8%$2,330$1,8304.66×
9%$2,802$2,3025.60×
10%$3,364$2,8646.73×

Year-by-year projection

YearBalanceInterest this yearTotal interestGrowth
Year 1$525+$25$251.05×
Year 2$551+$26$511.10×
Year 3$579+$28$791.16×
Year 4$608+$29$1081.22×
Year 5$638+$30$1381.28×
Year 6$670+$32$1701.34×
Year 7$704+$34$2041.41×
Year 8$739+$35$2391.48×
Year 9$776+$37$2761.55×
Year 10$814+$39$3141.63×
Year 11$855+$41$3551.71×
Year 12$898+$43$3981.80×
Year 13$943+$45$4431.89×
Year 14$990+$47$4901.98×
Year 15$1,039+$49$5392.08×
Year 16$1,091+$52$5912.18×
Year 17$1,146+$55$6462.29×
Year 18$1,203+$57$7032.41×
Year 19$1,263+$60$7632.53×
Year 20$1,327+$63$8272.65×

Growth chart

Balance growth over 20 years
$332$663$995$1kYr1Yr5Yr10Yr15Yr20
Principal
Interest earned

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